Golfers who go through periods of struggle at that level are quick to cite a host of excuses. Bad bounces, horrible lies, the occasional invisible spike mark, etc.
I will give Rickie Fowler this much credit - he doesn't blame his equipment when he sucks on the weekends. Sometimes it has little to do with the sticks being used and everything to do with a player's ability to actually execute and perform when the pressure is the greatest.
Just glossing over Reed's stats... he was ranked 41st in driving distance in 2016. This year he's ranked 84th. Putts per round average was 16th best last season. This season his PPR average has him at 64th.
How much of this is loft-related, versus confidence related? It's not like his driver loft changed over the past year, but he's losing about a half-club distance off the tee compared to last season. And putting... we all know that the two categories that matter most at this level are ultimately driving and putting, and he's down considerably in both those aspects.
Maybe he did have an issue with the loft of his irons being off, who knows. But it is very unlikely that his equipment is the crux of his problem this season.